| 摘要 |
PURPOSE:To prevent the spark plug from misfiring due to a cause of smolder, by providing a high voltage, that causes a creeping discharge on surfaces of insulator leg part when stuck a carbon to the insulator leg part, to the spark plug. CONSTITUTION:To a spark plug 10 of each cylinder is normally applied a high voltage of 2 KV by a first high voltage generator 100. With a carbon when sticking to an insulator leg part 14 to lower an insulation resistance of the spark plug 10, on surfaces of the insulator leg part is caused a creeping discharge that burns to cut off the carbon, which is converted into carbon dioxide (CO2) and automatically removed. In this way, an insulation resistance of the spark plug 10 is promptly restored to become a high resistance near infinity, and a high voltage, applied by a second high voltage generator 200, generates a spark discharge in spark gap between a centee electrode 11 and earth electrode 12 of the spark plug 10, thus a mixture can be well ignited to prevent a misfiring. |
